I don't see that as a guaranteed outcome if there's something like UBI to sustain demand, and automation to sustain supply.

UBI is only valuable if money is valuable though...what are you going to trade it for if no one has a job and everyone has access to super powerful production tools like advanced LLMs (which are at the low end of automated tooling overall)?

Idk, food and shelter?

"Vibe coding a house" will increase housing supply, (and automation at every step of supply chain too), but the costs will still be nonzero.

But just like labour, commodities are also going to go heavily down, exactly because of the automation you describe.

In addition, it's all fine and good to say "people will still need to buy food clothes an shelter"

But what is the price gonna be? Who can afford it if no one has a job? Who's going to sell it and to who? For what profit?